1. Field of the Invention
The present invention relates to a supply magazine for containing a recording material roll. More particularly, the present invention relates to a supply magazine for containing a recording material roll, in which the recording material roll can be stably in contact with a supply roller.
2. Description Related to the Prior Art
JP-A 10-291350 discloses a supply magazine used with a printer for containing a recording material roll. The supply magazine includes a magazine body and a magazine lid. The magazine body is loaded with the recording material roll. The magazine lid closes the magazine body openably. A rotatable supply roller is disposed in the magazine body. A drive mechanism in the printer rotates the supply roller, and advances the recording material roll from the supply magazine to the inside of the printer. The advance of the recording material roll should be reliable. To this end, a pushing mechanism is disposed in the supply magazine for pushing an outermost turn of the recording material roll to the supply roller in a constant manner.
The pushing mechanism includes a retention lever and a spring. The retention lever is movable between retaining and releasing positions. The retention lever, when in the retaining position, presses the recording material roll against the supply roller, and when in the releasing position, discontinues applying pressure to the recording material roll. The spring is secured between the retention lever and the magazine lid. When the magazine lid is opened, the spring pulls the retention lever to the releasing position. When the magazine lid is closed, the retention lever is pushed by the spring to the retaining position.
However, the magazine lid swings in a large range of a rotational angle. The spring must extend and compress according to the swinging range, and is likely to be deformed or crept. The pushing mechanism according to the prior art has shortcomings in low reliability.
In view of the foregoing problems, an object of the present invention is to provide a supply magazine for containing a recording material roll, in which a pushing mechanism can keep the recording material roll stably contacted on a supply roller.
In order to achieve the above and other objects and advantages of this invention, a supply magazine contains a recording material roll constituted by continuous recording material wound in a roll form, the recording material being fed by a supply roller. In the supply magazine, a magazine body receives the recording material roll. A magazine lid closes the magazine body openably. At least one retention lever is shiftable between retaining and releasing positions, for pressing an outermost turn of the recording material roll to the supply roller when in the retaining position, and for releasing the recording material roll from the supply roller when in the releasing position. A linking mechanism has first and second ends, the first end being connected with the magazine lid, the second end being connected with the retention lever, the linking mechanism shifting the retention lever from the releasing position to the retaining position in response to closing of the magazine lid.
Furthermore, a magazine opening is formed in the magazine body and closed by the magazine lid. A hinge mechanism is secured to an edge of the magazine opening, for keeping the magazine lid pivotally movable on the magazine body between closed and open positions.
In a preferred embodiment, the supply magazine comprises the supply roller contained in the magazine body.
Furthermore, an exit passageway is formed in the magazine body and close to the supply roller, for exiting the recording material.
Furthermore, a roll holder is secured to a rotational axis of the recording material roll, has first and second axial end parts, supports the recording material roll. The at least one retention lever comprises first and second retention levers for pushing respectively the first and second axial end parts directly or indirectly.
The magazine lid and the magazine opening are disposed at a top of the magazine body, and the exit passageway is formed in a lower wall of the magazine body. Furthermore, a lower lid closes the exit passageway openably.
Furthermore, first and second support plates are disposed in the magazine body, and opposed to each other. First and second cutouts are formed through the first and second support plates, for receiving insertion of the first and second axial end parts. The first and second retention levers push portions of respectively the first and second axial end parts located outside the first and second support plates.
The linking mechanism includes at least first and second linking plates, the first linking plate having the first end and a third end, the second linking plate having the second end and a fourth end connected with the third end in a pivotally movable manner, the first and second linking plates transmitting rotation of the magazine lid to the retention lever when a rotational position of the magazine lid is within a limited section between the closed and open positions.
Furthermore, a bias mechanism biases the retention lever toward the releasing position when the retention lever is between one intermediate position and the releasing position, and biases the retention lever toward the retaining position when the retention lever is between the intermediate position and the retaining position.
Furthermore, a pivotal pin supports the retention lever on the magazine body in a pivotally movable manner. The bias mechanism includes a tension coil spring. A first securing portion secures one end of the tension coil spring to the magazine body. A second securing portion is disposed in the retention lever and on an extension of a line where the first securing portion and the pivotal pin lies, for securing a remaining end of the tension coil spring to the retention lever.
The magazine lid, while swung toward the closed position, pushes the third or fourth end, and causes the second linking plate to swing the retention lever to the retaining position. The magazine lid, while swung toward the open position, causes the first linking plate to pull the second linking plate, and swings the retention lever to the releasing position.